The company said it has shown a 100 percent success rate in the lab. A new birth-control pill for men has been patented in the U.S. and could tap into a lucrative worldwide market in five to seven years, officials said yesterday.

The Quebec-based biotech firm Immucon described its male contraceptive technology, which the company said has shown a 100 percent success rate in the lab, as able to “neutralize the sperm’s fertilizing capacity.”

“It’s like if someone places a toothpick in the keyhole so the key no longer is able to open the lock,” Alain Bosse, president of Immucon, said in a telephone interview.

The “oral vaccine,” which lasts about 12 months and is completely reversible, is expected to go into human trials shortly. It has no known side effects.

“We have been told there is great worldwide interest in this, and we may be able to go through an accelerated process” of Food and Drug Administration approval, Bosse said.

Immucon said the market for the drug is lucrative, estimating it at about $850 million.

“Current contraceptive methods are still inadequate,” the company said. “Hormonal methods, which dominate the market, are targeted essentially toward the women and still present side effects.”

“For some women, the side effects are unacceptable,” Bosse added. “And because a male pill could allow men to share responsibility for birth control with women, we think we have a very good alternative, a new alternative.”

Immucon, a 6-year-old firm specializing in contraception and fertility, said surveys have so far shown there is a high “acceptance level” for a male pill.

To date, Immucon has developed a male-infertility diagnostic test designed to avoid invasive procedures that women usually must undergo to help identify the source of infertility.